Why is three fourths and four eights not equivalent fractions?

Answer 1

Well basically three fourths is 3 quarters and 4 eights is equivalent to a half so 3/4 is bigger than 1/2 by 1/4

Second Answer:

For example, 12/16 is an equivalent fraction of 3/4 and 8/16 is equivalent to 4/8. Look at them side by side:

12/16 8/16

If you notice, the denominator of both is the same. 12 is not the same as 8, so 3/4 and 4/8 are different. (Another way to look at it is to reduce 4/8 to 2/4. Look at it that way.)